In theory, Homebrew should solve this, but I've just had so many bad experiences with it over the years, I won't touch it. All the problems you can imagine from trying to tell a non-techy friend over voice, without screensharing, how to do all that stuff you just listed? Brew seems to make those same mistakes half the damned time, and leave your system / the app in a weird, half-installed state. It seems like most app devs have come to the same conclusion and just make actually good installers. It's unfortunate that it's come to that, but there ya go. I honestly have no idea if that's a Homebrew problem or if it's just doing its best with what apple gives it to work with, but either way.
I've had better experiences with Chocolatey on Windows, but for casual / everyday use it's just so rare I need to install something that doesn't have its own nice installer, so I very rarely run it.
I call BS. I think this is something that people like to think that they believe, but they really don't.
The first time they found themselves standing in the kitchen and thinking, "How long am I supposed to cook chicken?" and realizing the only way to find out is to clean up, get dressed, drive down to the bookstore and find a cooking-for-beginners book (or, if they're lucky and know somebody who would know the answer, they could try to call them, but it would only work if that person was home and able to hear their landline and felt like gambling on answering an unknown call - unless they maybe had caller ID), they'll be right back on board with the digital age.
Like, go watch early-seasons episodes of The X-Files and realize how many of the plot lines only work because the show started in a time that was pre-mobile phones, and then realize that kind of hilariously stupid and inconvenient situation was just, like, everyday life for everybody not so very long ago. Plan to meet a friend for lunch but they don't show up? You can decide to wait and risk eating alone, or go home, because there's literally no way to find out if they're just running a little late or if they're completely unable to come or what.
Sure, social media is a bit of a hellscape, but there is so much convenience that people take for granted that comes from cell phones and internet. I just do not believe more than a single-digit percentage of people would seriously enjoy going back for more than a few days, tops. No more than a camping trip.